Bobbin changer for sewing machines



April 9, 1968 F. J. SCHIFFMACHER E AL 5,

I BOBBIN CHANGER FOR SEWING MACHINES Filed Feb. 1, 1966 5 Sheets-Sheei 1INVE TORS.

FRED J. SCHIFFMACHER BY WALTER A. ROMAN A TTORNEYS.

April 9, 1968 F. J. SCHIFFMACHER ET'AL 3,376,838

BOBBIN CHANGER FOR SEWING MACHINES Filed Feb. 1, 1966 I 5 Sheets-Sheet7i INVENTORS.

. FRED a. SCHIFFMACHER BY WALTER A. ROMAN WWFZM United States PatentBOBBlN CHANGER FOR SEWING MACHINES Fred J. Schiifmacher, New Canaan, andWalter A.

Roman, Nor-walk, Conrn, assignors, by mesne assignments, to IvanhoeResearch Corporation, New

York, N.Y., a corporation of Delaware Filed Feb. 1, 1966, Ser. No.524,222 8 Claims. (Cl. 112-186) ABSTRACT OF THE DISCLOSURE A bobbinchanger for sewing machines including a carrier for carrying an assemblyof bobbin and case from a magazine to the holder with transfer means formoving the assembly from the carrier into the holder, the transfer meansalso removing the assembly from the holder when the bobbin has beendepleted. An opening in the carrier for reception of the bobbin assemblyinto the carrier is positioned adjacent to and aligned with the magazineto receive a bobbin assembly therein and in a second position of thecarrier this opening is adjacent to and aligned with the holder fortransferring the bobbin assembly into the holder. The transfer meansincludes a movable hook to push the bobbin assembly from the carrierinto the holder, this hook being engageable with the pivoted latchingelement on the bobbin case for releasing the assembly from the holder toremove the deplete-d assembly, with the operations carried out insequence providing a quick automatic replacement of the depleted bobbinassembly.

The invention relates to a bobbin changer for sewing machines.

In the operation of sewing machines for factory production work twodifferent procedures. have been followed for the removal and replacementof used bobbins. In the case of work entailing fairly long sewingoperations, the operator tends to rewinding of a spare bobbin whileperforming the sewing operation; but where the sewing operations are ofbrief duration a supply of rewound or new bobbin spools will generallybe kept at hand for replacement of the used bobbins as needed. In eithercase the bobbin changing procedure is a rather fussy, timeconsumingoperation involving as it does the several steps of (1) Unlatching andpulling out the bobbin assembly from the basket of the bobbin holder;

(2) Removing the used bobbin spool from its case;

( 3) Placing the new or rewound spool in the empty case from step 2; and

(4) Placing the new bobbin assembly from step 3 into the basket of theholder and pressing it in to latch it in place.

These several steps all must be performed while the machine is stoppedand thus add to the idle time during which the investment in the machineis earning no return. Also, the performance of these steps adds to thestrain on the operator, dissipating energy which otherwise would beavailable for productive effort.

It has been an object of our invention to provide a bobbin changingsystem and machine which simplifies the procedure and makes it possibleto change bobbins by the actuation of an automatic changer mechanism.Our bobbin changer does not operate according to the manual proceduresheretofore followed, but performs the several steps in adifferent'manner and sequence as will be explained.

Summary Our invention is applicable to any conventional form of sewingmachine which includes a bobbin holder. The

3,376,838 Patented Apr. 9, 1968 bobbin 'holder generally comprises arotary hook within which is rotatably mounted a basket which receivesthe bobbin assembly comprised of the bobbin spool and the case for suchspool. A latch on the case holds it in place in the basket of the bobbinholder. As applied to such a machine our bobbin changer comprises (a) amagazine holding in axial alignment a number of bobbin assemblies eachcomprising a bobbin and a bobbin case, the bobbin being assembled intothe case,

(b) a bobbin carrier movable between a position in which it is alignedwith the magazine to receive a bobbin assembly from the magazine andanother position in which the carrier is aligned with the bobbin holder,

(c) transfer means for moving the bobbin assembly from the carrier tothe bobbin holder and for removing the bobbin assembly from the holderwhen the bobbin is substantially empty, and

(d) means for activating the transfer means and bobbin carriersequentially for removal of a bobbin assembly from the holder, moving ofa new bobbin assembly from the magazine to align it with the holder andfor transfer of the new bobbin assembly to the holder.

The transfer means (c) for moving the bobbin from the carrier to thebobbin holder and for removing the bob-bin from the holder includes amovable hook which is arranged to push the bobbin from the carrier intothe bobbin holder, and the hook also is arranged to grasp the bobbin asthe hook retracts for removing the bobbin from the holder.

The bobbin carrier receives the bobbin assembly from the magazine in oneside of the carrier and the transfer means moves the bobbin assembly tothe bobbin holder from the same side of the carrier. The carrier whenaligned with the bobbin holder is positioned directly adjacent theholder.

Other features will appear as the description proceeds.

Description We shall now describe the best mode contemplated by us forcarrying out our invention, referring to the accompanying drawings inwhich:

FIG. 1 is a perspective view showing the general arrangement of ourbobbin changer mechanism,

FIGS. 2, 3 and 4 are detail operational views showing essential portionsof the principal elements of the mechanism,

FIG. 2 showing the carrier aligned with the empty bobbin holderpreparatory to loading a new bobbin into the holder,

FIG. 3 showing the transfer means at the end of its loading movement,and

FIG. 4 showing the movable hook of the transfer means retracted forengagement with the pivoted latching element of the bobbin case forreleasing the bobbin assembly from the holder and ready to pull theassembly away from the holder as the pivoting arm of the transfer meansretracts.

FIG. 5 is a circuit diagram for the electrical controls to activate theseveral operating components of the bobbin changer mechanism.

FIG. 6 is a schematic representation of the timing for sequentialoperation of the several operating components.

Referring to FIG. 1, in which the bobbin holder of a conventional sewingmachine is indicated at H, our bobbin changer comprises (a) magazinemeans M for holding in alignment a number of bobbin assemblies 1 eachcomprising a bobbin and a bobbin case 2, the bobbin being assembled intothe case,

(b) a bobbin carrier C movable between a first position, FIGS. 1 and 4,in which the carrier is aligned with the magazine M to receive a bobbinassembly from the magazine and a second position, FIGS. 2 and 3, inwhich the carrier is aligned with the bobbin holder H,

() transfer means T for moving the bobbin assembly from the carrier tothe bobbin holder and for removing the bobbin assembly from the holderwhen the bobbin in substantially empty, and

(d) means 3, 4 for activating the transfer means T and bobbin carrier Csequentially for removal of a bobbin assembly from the holder, moving ofa new bobbin assembly from the magazine M to align it with the holder Hand for transfer of the new bobbin assembly to the holder.

The transfer means T for moving the bobbin from the carrier to thebobbin holder and for removing the bobbin from the holder includes apivoting arm 5 (pivoted as at 6 to the frame 7 of the machine) and asolenoid-actuated hook 8 recipro-cably mounted on arm 5, the pivotingarm arranged to push the bobbin from the carrier into the bobbin holder,FIG. 3, and the solenoid-actuated hook 8 arranged to grasp the bobbin,FIG. 4, as the pivoting arm 5 retracts for removing the bobbin from theholder.

As applied in the use of bobbin assemblies in which the bobbin case 2includes a pivoted latching element 9, FIG. 4, for releasing the bobbinassembly from the bobbin holder, the solenoid-actuated book 8 isarranged to engage the pivoting latching element 9 of the bobbin casefor releasing the bobbin assembly from the holder and pulling theassembly away from the holder as the pivoting arm 5 retracts.

In our preferred construction, the activating means includes a sensorelement 10 engageable by a bobbin assembly 1 received by the bobbincarrier C from the magazine, this sensor element being interlocked withan electrical control circuit, FIG. 5, forming part of the activatingmeans to prevent activation of the carrier until the sensor element isengaged by a bobbin assembly in the manner shown in FIG. 4. (In FIGS. 2and 3 the sensor finds no bobbin assembly engaging it.)

We have found it particularly advantageous to construct the bobbinchanger in the manner shown wherein the bobbin carrier C receives thebobbin assembly from the magazine M in one side of the carrier and thetransfer means T moves the bobbin assembly to the bobbin holder H fromthe same side of the carrier. For best operating results it is alsoquite essential that when the carrier is aligned with the bobbin holder,the carrier be positioned directly adjacent the holder in the mannerclearly shown in FIGS. 2 and 3.

In the preferred construction illustrated, the magazine M comprises atubular container 11 whose axis is normal to the path of movement of thecarrier C, and such magazine includes spring means for urging the bobbinassemblies aligned within the magazine toward the carrier. We have useda flat coil spring of the constant rewind tension type known as a Hunterspring, the coiled portion of which is shown at 12 and the unwoundportion of which is shown at 13. The unwound portion is anchored to thebase 14 by which the magazine is mounted on the frame 7 of the machine.The carrier includes an opening 15, FIG. 4, through which the bobbinassemblies pass for reception into the carrier and a barrier strip 16extending lengthwise beyond such opening so that when the carrier movesinto its second position, FIGS. 2 and 3, in alignment with the bobbinholder, the discharge end of the magazine is covered by the barrierstrip to hold the bobbin assemblies within the magazine until releasedone by one each time the empty carrier returns to its first position,FIGS. 1 and 4.

The carrier C as shown, besides having an opening at one side to receivea bobbin assembly, also has an opening 17 at the other side to allowentry of the hook 8 of the transfer means T for moving the bobbinassembly from the carrier to the bobbin holder. Opening 17 not onlyextends through the other side of the holder but also through the endthereof as can be seen in FIG. 1, thus allowing the hook 8 to passthrough the side and end of the holder in reaching the position shown inFIG. 3.

Activating means 3 and 4 may include fluid-actuated pistons operatingwithin cylinders 18 and 19, cylinder 18 being pivoted at its base as at20 to a clevis 21 mounted on a bracket 22 secured to the frame 7 of themachine. Piston rod 23 extending from the end of the cylinder is pivotedas at 24 to the pivoting arm 5 of transfer means T. Cylinder 19 is fixedto the frame 7 of the machine and its piston rod terminates in a clevis25 secured to the carrier C. Carrier C may have a flanged base engaginga guide track 26 along which the carrier travels in its movementsbetween the magazine and the holder.

As an aid in removing the used bobbin assemblies from the holder H, oneor more suitable air jets may be employed, these being arranged in themanner shown at 27, 28 and connected to a suitable source of compressedair (not shown).

In practice the circumference of the bobbin case must be properlyaligned with the basket of the holder. The basket is indexed in apredetermined position opposite the sewing machine needle N as by meansof a projection on the arm 29, FIG. 2, suitably mounted above theholder, such projection engaging the basket adjacent the opening for theneedle. The bobbin case in turn is indexed relative to the basket andthis may be accomplished by having a projection on the bobbin case (orof the latching mechanism thereof) engage a groove in the magazine M anda similar groove in the carrier C, the projection of the bobbin casebeing slideably engaged in these grooves. Thus when the transfermechanism is actuated, hook 8 will deliver the bobbin assembly to theholder in proper alignment with the indexed position of the basket ofthe holder.

FIG. 5 illustrates one suitable electric circuit for operating thevalves of cylinders 18 and 19 and the solenoid of the transfer means T.Conventional symbols are used. Switch 1 controls the solenoid for thevalve of cylinder 19 for actuation of the carrier C as it moves from themagazine to the holder and back again. Switch 2 controls the operationof the solenoid of a valve for the cylinder 18 which controls thepivoting movements of the transfer means T toward and away from thebobbin holder. Switch 3 controls the solenoid for actuation of thereciprocating hook 8 as it extends to pass around the end of the bobbinlatch and then retracts to engage such latch in the manner shown in FIG.4. Limit switch 1 is actuated by the sensor element 10 so as to preventoperation of the carrier from its FIG. 1 position until the carrier hasreceived a bobbin assembly from the magazine.

FIG. 6 explains the sequence of operation according to which the cyclebegins at the point that a used bobbin is to be removed from the holder:The book 8 extends; pivoting arm 5 moves toward the holder and at thelimit of such movement hook 8 retracts to engage the bobbin latch 9 inthe manner shown in FIG. 4; arm 5 swings away, removing the bobbin fromthe holder; once removed, the bobin drops through the opening 30 in theframe of the machine; the carrier moves opposite the holder; arm 5pivots toward the holder to deliver the new bobbin into the holder; andfinally arm 5 swings away and carrier C moves opposite the magazine atwhich point barrier 16 opens the end of the magazine permitting anothernew bobbin to pass into the holder. The switches may be controlled inany known manner as by means of a suitable clock mechanism (not shown).The clock mechanism may be operated according to a predetermined settingof the cycle which may be initiated by a manual switch or by a switchcontrolled by a counted mechanism in turn actuated by the operation ofthe sewing machine. An electric motor M is shown in this example fordriving the clock mechanism.

A control relay CR-l has its winding connected in parallel with thesolenoid for the valve of cylinder 19. This control relay includes apair of normally open contacts which are in shunt with the limitswitch 1. They become closed upon energization of the relay winding andserve to continue the movement of the carrier C over to the holder Heven though the limit switch 1 may have become opened after the carrierC begins its movement.

The terms and expressions which we have employed are used in adescriptive and not a limiting sense, and we have no intention ofexcluding equivalents of the invention described and claimed.

We claim;

1. In a sewing machine including a bobbin holder, 6. bobbin changercomprising (a) magazine means for holding in alignment a number ofbobbin assemblies each comprising a bobbin and a bobbin case, the bobbinbeing assembled into the case,

(b) a bobbin carrier slidable between a first position in which thecarrier is aligned with the magazine to receive a bobbin assembly fromthe magazine and a second position in which the carrier is aligned withthe bobbin holder,

(0) transfer means for moving the bobbin assembly from the carrier tothe bobbin holder and for removing the bobbin assembly from the holderwhen the bobbin is substantially empty, and

(d) means for activating the transfer means and bobbin carriersequentially for removal of a bobbin assembly from the holder, moving ofa new bobbin as; sembly from the magazine to align it with the holderand for transfer of the new bobbin assembly to the holder.

2. In a sewing machine including a bobbin holder for holding a bobbinassembly in position near the sewing machine needle, an automatic bobbinchanger comprising (a) magazine means for holding in alignment a numberof bobbin assemblies, each assembly comprising a bobbin and a bobbincase, the bobbin being assembled into the case,

(b) a bobbin carrier for carrying a bobbin assembly from the magazine tosaid holder, said carrier having an opening therein adapted to receivethe bobbin assembly enclosed within the carrier,

(c) said carrier being movable between a first position in which saidopening is adjacent to and aligned with the magazine to receive a bobbinassembly from the magazine and a second position in which said openingis adjacent to and aligned with the bobbin holder in readiness fortransferring the bobbin assembly from said opening into the holder,

(d) means for automatically moving said carrier from said first positionto said second position and for returning said carrier back to saidfirst position,

(e) transfer means for moving the bobbin assembly from said opening inthe carrier into the bobbin holder and thereafter for removing thebobbin assembly from the holder when the bobbin is substantially empty,

(f) said carrier receiving the bobbin assembly from said magazine intosaid opening on one side of said carrier, and said transfer means movingthe bobbin assembly from said opening on the same side of the carrier,and

(g) means for activating said transfer means to move the bobbin assemblyfrom said opening into the holder when said carrier is in said secondposition and to remove the bobbin assembly from the holder when saidcarrier is in said first position.

3. In a sewing machine including a bobbin holder for holding a bobbinassembly in position near the sewing machine needle, an automatic bobbinchanger as claimed in claim 2, wherein each bobbin assembly comprises abobbin and a bobbin case, the bobbin being assembled into the case, andthe case having a pivoted latching element for holding the assembly inthe holder and for re leasing the assembly from the holder, and in whichsaid transfer means (e) includes a movable hook, said activating means(g) moving said hook to push the bobbin assembly from said opening inthe carrier into the holder when said carrier is in said secondposition, said hook being engageable with said pivoted latching elementof the bobbin assembly to be removed from the holder, and saidactivating means engaging said movable hook with said pivoted latchingelement and retracting said book for releasing the assembly from theholder and pulling the assembly away from the holder to remove theassembly from the holder when said carrier is in said first position.

4. In a sewing machine including a bobbin holder for holding a bobbinassembly in position near the sewing machine needle, an automatic bobbinchanger as claimed in claim 2, in which said carrier is movable along atrack from said first position to said second position, said carrier insaid second position being located between said holder and said transfermeans, said opening in said carrier extending through said carrier tothe opposite side thereof, and said transfer means entering said openingon the opposite side from said holder for pushing the bobbin assemblyfrom said carrier into the holder.

5. In a sewing machine including a bobbin holder adapted to hold abobbin assembly comprising a bobbin and a bobbin case, the bobbin beingassembled in the case when said case is held in the holder, an automaticbobbin changer for removing from the holder an assembly having adepleted bobbin and for leading into the holder another bobbin assembly,said automatic bobbin changer comprising (a) transfer means engageablewith a depleted assembly in the holder for removing the assembly fromthe holder,

(b) means for operating the transfer means to move the transfer meansfrom an initial position to engage the depleted assembly and remove theassembly from the holder,

(c) magazine means for holding a number of bobbin assemblies,

(d) a carrier comprising an enclosure with an opening therein forreceiving the bobbin assembly therein, said carrier movable bet-ween afirst position in which the carrier is aligned with the magazine toreceive a bobbin assembly from the magazine and a second position inwhich the carrier is aligned with the holder for loading the assemblyinto the holder,

(e) means for moving the carrier from said first position to said secondposition and for returning said carrier to said first position,

(f) timer means for controlling said operating means and said movingmeans to actuate said moving means to move said carrier to said secondposition after the depleted assembly has been removed from the holder,and

(g) said timer means thereafter actuating said operating means causingsaid transfer means to load the bobbin assembly from said carrier intothe holder while said carrier is in its second position and then to movesaid transfer means back to its initial position and to return saidcarrier to its first position.

6. In a sewing machine machine including a bobbin holder, a bobbinchanger comprising (a) a magazine means for holding in alignment anumber of bobbin assemblies each comprising a bobbin and a bobbin case,the bobbin being assembled into the case,

(b) a bobbin carrier movable between a first position 7 in which thecarrier is aligned with the magazine to receive a bobbin assembly fromthe magazine and a second position in which the carrier is aligned withthe bobbin holder,

(c) transfer means for moving the bobbin assembly from the carrier tothe bobbin holder and for rernoving the bobbin assembly from the holderwhen the bobbin is substantially empty, and

(d) means for activating the transfer means and bobbin carriersequentially for removal of a bobbin assembly from the holder, moving ofa new bobbin assembly from the magazine to align it with the holder andfor transfer of the new bobbin assembly to the holder,

(e) said magazine comprising a tubular container whose axis is normal tothe path of movement of the carrier, and in which such magazine includesspring means for urging the bobbin assemblies aligned within themagazine toward the carrier, and

(f) said carrier (b) includes an opening through which the bobbinassemblies pass for reception into the carrier and a barrier stripextending lengthwise beyond such opening so that when the carrier movesinto its second position in alignment with the bobbin holder thedischarge end of the magazine is covered by the barrier strip to holdthe bobbin assemblies (3 within the magazine until released one by oneeach time the empty carrier returns to its first position.

7. In a sewing machine according to claim 1, the construction in whichthe carrier (b) comprises a member having an opening at one side toreceive a bobbin assembly and having an opening at the other side toallow entry of the transfer means for moving the bobbin assembly fromthe carrier to the bobbin holder.

8. In a sewing machine according to claim 1, the construction in whichthe carrier (b) comprises a member having an opening at one side toreceive a bobbin assembly and an opening extending through the otherside and the end of said member to allow entry of the transfer means formoving the bobbin assembly from the carrier to the bobbin holder.

References Cited UNITED STATES PATENTS 975,155 11/1910 Pepperling 1121862,298,871 IO/1942 Cumfer 112186 2,438,459 3/1948 Sebel 112-186 2,507,4705/1950 Hirsch 112181 2,690,725 10/1954 Schumann 112186 2,733,676 2/1956Schumann 112180 2,808,795 10/1957 Wortham 112-186 X HERBERT F. ROSS,Primary Examiner.

